Chronium supplements help this that.. otherwise get Xylitol. I love it. It doesnt feed the nasties, tastes and looks just like sugar, is alkalising AND said to be mildly antifungal (as its a natural product derived from birch trees).
If you get it go for the birch tree one - not the version from corn (could be sprayed, Genetically-Modified etc).
Plamil do a DELICIOUS alternative safe choc bar made with shelled hemp and Xylitol... yum indeed!